In Pokémon HeartGold and SoulSilver after beating the Elite 4 for the first time you will be able to recieve the National Dex from him. Also after defeating all of the Johto and Kanto gym leaders he will give the trainer the HM08 Rockclimb.

In-game Pokémon

Pikachu - (In Pokémon Yellow, he is briefly shown catching the player's starter, Pikachu, however he later gives it to the player.

At Pokémon Yellow, Professor Oak was going to be a person that would battle you after you beat the champion. He would have a Tauros, Exeggutor, Gyarados, Arcanine and the starter that opposes your starter Pokémon at it's final form. It was cut from the game and it can only be accessed through glitches.

In the Pokémon Adventures Manga

In the Manga

Just like in the games, he is highly regarded and known, he is the person who gives Pokédexes to the Pokédex Holders. His grandson is Blue. In Pokémon Electric Tale of Pikachu, his Charmeleon, named Char, evolved into Charizard.

In Anime

In the anime, Oak is most notable for his vast research facility, where he cares for and studies hundreds of Pokémon, including those owned by, but not currently traveling with, Trainers from Pallet Town. He has confidence in his grandson, Gary Oak, but more often joins Ash's mother and friends in cheering on Ash in his competitions.

In the novelizations written by Takeshi Shudō, Professor Oak comes from a prestigious family. He has two brothers, one is the mayor of Pallet Town and the other is the Post Master, and his grandfather was the first Trainer from Pallet Town to receive widespread recognition. According to Professor Elm, Professor Oak's studies and research mostly focus on how humans and Pokémon interact with each other.

He appears as a young boy, Sam (Japanese: ユキナリ Yukinari) in the fourth film, Celebi: Voice of the Forest. Ash befriends the young Oak, who, due to traveling from 40 years in the past, is around the same age as him. The revelation that Sam is Oak, while able to be speculated because Oak's first name was revealed in the second movie, The Power of One, comes only at the end of the movie, when Oak knows that Ash's friend's name was Sam despite Ash never telling him so, and Tracey finding the sketchbook in which young Sam drew Pikachu sleeping with Celebi in Oak's closet.

Oak lives up the road from Ash's mother and the two often appear together as they are very good friends. He currently lives with Tracey Sketchit, who became his loyal assistant in The Rivalry Revival. Tracey and Prof. Oak are very passionate about studying Pokémon and are both artists.

Professor Oak as a child

In the movie, Sam saw many Generation II Pokémon, notably the legendary Pokémon Celebi and Suicune, though his Pokédex only catalogs the Generation I Pokémon, claiming that they are all the Pokémon that the world knows, in the Kanto arc. This discrepancy is likely due to the retcon that occurred when the 100 new Pokémon were introduced to the series, and due to the ever-increasing number of Pokémon, with Pokémon from Generation II, Generation III, and Generation IV being able to be trained in Kanto during FireRed and LeafGreen and HeartGold and SoulSilver, this is likely the reason that the number of them as of the current generation of games is no longer mentioned in the anime.

Pokémon

On hand

Pokémon

Information

Dragonite is the powerhouse of Oak's. When invited to see Mirage Pokémon come to life, Oak decided to take Dragonite just in case problems arose. Problems did arise however when Professor Yung made a mirage Mewtwo that started to attack others. Dragonite was among the Pokémon who were used to try and stop it, to no avail.

Professor Oak used Pidgey when there was a contest between him and an imposter, who was actually James, on who is the real Professor Oak. Using Pidgey to attack Team Rocket, Oak muses that it's not the size of the Pokémon that determines its strength and Pidgey was the perfect example of this.

Status Unknown

Pokémon

Information

When he traveled through time, Charmeleon was one of the Pokémon that Sammy used to try and defend Celebi from The Iron Masked Marauder. Charmeleon is a powerful Pokémon that can hold its own in battle. It's current status 40 years later is unknown.